 
 (defn make-bird
   "Make a new bird with the specified program. At the specified location."
-  [position]
-  (-> {}
-      (make-real)
-      (make-box)
-;      (make-sphere)
-      (assoc :type :bird
-             :color [1 0 0]
-             :position position)
-      (make-collision-shape)))
+  [position]  
+  (make-real {:type :bird
+              :color [1 0 0]
+              :position position
+              :shape (create-box)}))
   
 (defn random-bird
   "Make a new random bird."

(defn initialize-simulation
  "This is the function where you add everything to the world."
  []
  (let [birds (repeatedly num-birds random-bird)
        floor (make-floor)]
    {:objects (conj birds floor)}))

(start-gui initialize-simulation update-world 0.1)

(def num-birds 30)
(def avoidance (atom 0.2))
(def clustering (atom 0.1))
(def centering (atom 0.03))

(def max-acceleration 2)

